Open AccessInterhemispheric plasma flows in the equatorial topside ionosphere
Author(s) -
Venkatraman Sarita,
Heelis Rod
Publication year - 2000
Publication title -
journal of geophysical research: space physics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.67
H-Index - 298
eISSN - 2156-2202
pISSN - 0148-0227
DOI - 10.1029/2000ja000012
Subject(s) - solstice , longitude , latitude , ionosphere , atmospheric sciences , southern hemisphere , f region , altitude (triangle) , geology , satellite , northern hemisphere , local time , physics , geodesy , environmental science , climatology , geophysics , astronomy , geometry , statistics , mathematics
Latitudinal, longitudinal, and seasonal variations in the field‐aligned and perpendicular flows measured at an altitude near 830 km, by the Defense Meteorological Satellite Program F 10 satellite are examined. These profiles are studied during the nighttime (2100 magnetic local time) for solstice periods in 1991 when the solar activity is high. Latitude and longitude variations show the influence of F region winds in modulating the observed field‐aligned flows. At night, large downward field‐aligned flows of the order 400–600 ms −1 are observed in the winter hemisphere and coincide in longitude with the location of previously identified adiabatic heating effects studied by Venkatraman and Heelis [1999a], Interhemispheric flows at 2100 hours local time are seen to extend up to apex heights of ∼ 1000 km during times of high solar activity. Perpendicular drifts, however are relatively invariant with latitude as expected.